Challenges come in different forms. Sometimes it's a matter of a student purposely trying to come up with something the teacher cannot answer.

Dustin fell into this category. He would come early to class just to ask one of his multitudinous questions. It wasn't so much that he wanted to know the answer as that he wanted to find something to stump me.

Usually, it was a simple matter of finding a solution to this ninth-grader's questions. Sometimes, it wasn't so simple.

One day, Dustin asked me if light could die.

Light can be refracted, reflected, or absorbed, but can it just disappear?

I thought about different types of light, from gamma rays to radio waves. I thought about sources of light, from suns to quasars. Then I had an answer I was comfortable with.

Astronomers have "seen" objects billions of light-years away. The photon of light coming from these objects had to have existed that long. If the light didn't die in all those years, it most likely can't.

I don't know if my reasoning helped Dustin, but it did require me to stretch myself.

Other students enjoy discovering a teacher's weak areas and pointing it out for all to see.

Brady was one of these. He always recognized when you weren't sure of your knowledge and he was never shy about letting you know.

The first time he tried it with me I reacted predictably. I bristled. Later, when I calmed down, I had to admit he was right. I do have a hard time learning names.

I soon came to think of Brady not as one of my physical science students, but as a potential first-class prosecutorial attorney. I came to expect and respect his attacks on the weaknesses of my arguments.

At least once it solved a real problem for me.

The concept of terminal velocity can be hard for students.

They can't see why, if the force of the air pushing up on an object as it falls is equal to the force of gravity pulling down on it, the object doesn't come to a stop.

I had struggled to find an explanation but never really came up with one - until Brady pointed it out to me.

"Miss Spencer, you are saying the air is pushing up on the object, but isn't the object really pushing down on the air?" he asked.

Of course, that was the key I had overlooked. Falling or not falling depends on what is doing the pushing - the air or the object.

Then there are the students who get caught up in wrong assumptions.

Hector frequently told me I didn't know what I was talking about.

When I said that long-handled wheel barrels were used to move heavy things he quickly informed me I was out of my mind.

I didn't accept that, and invoked the power of my position to put him down. After a few such incidents with him I realized the problem: false assumptions.

When I used the term "long-handled" he asssumed that I meant 20 or 30 feet long.

Through Hector I learned that the next time a student objects to a statement of mine, I need to check on his understanding of what I meant before I get upset.

Does it annoy me to have students try to trip me up, point out my weak spots, or flat out tell me I'm wrong?

You bet it does.

But as a teacher, it is far more important for me to swallow my pride, listen to my students with an open mind, and celebrate the fact that today's uninhibited students provide me with unforgettable learning experiences.